I also commute in the rain and yes visibility is key for me too. I even wear a reflective vest on top of my orange rain jacket. These $7 vests you can buy at Amazon.
https://www.amazon.com/Neiko-53941A-...eflective+vest
In addition two lights at front and rear each. Especially at these rainy days I have to switch from trails to suburban roads. Most of the paved trails are running through woods and are getting really slippery since they are fully covered with leaves or have dirt washed across the trails. I already had a few close calls and avoid them during or after rain.